git-annex/Git/Config.hs

151 lines
4.6 KiB
Haskell

{- git repository configuration handling
-
- Copyright 2010-2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.Config where
import qualified Data.Map as M
import Data.Char
import System.Process (cwd, env)
import Common
import Git
import Git.Types
import qualified Git.Construct
import Utility.UserInfo
{- Returns a single git config setting, or a default value if not set. -}
get :: String -> String -> Repo -> String
get key defaultValue repo = M.findWithDefault defaultValue key (config repo)
{- Returns a list with each line of a multiline config setting. -}
getList :: String -> Repo -> [String]
getList key repo = M.findWithDefault [] key (fullconfig repo)
{- Returns a single git config setting, if set. -}
getMaybe :: String -> Repo -> Maybe String
getMaybe key repo = M.lookup key (config repo)
{- Runs git config and populates a repo with its config.
- Avoids re-reading config when run repeatedly. -}
read :: Repo -> IO Repo
read repo@(Repo { config = c })
| c == M.empty = read' repo
| otherwise = return repo
{- Reads config even if it was read before. -}
reRead :: Repo -> IO Repo
reRead r = read' $ r
{ config = M.empty
, fullconfig = M.empty
}
{- Cannot use pipeRead because it relies on the config having been already
- read. Instead, chdir to the repo and run git config.
-}
read' :: Repo -> IO Repo
read' repo = go repo
where
go Repo { location = Local { gitdir = d } } = git_config d
go Repo { location = LocalUnknown d } = git_config d
go _ = assertLocal repo $ error "internal"
git_config d = withHandle StdoutHandle createProcessSuccess p $
hRead repo
where
params = ["config", "--null", "--list"]
p = (proc "git" params)
{ cwd = Just d
, env = gitEnv repo
}
{- Gets the global git config, returning a dummy Repo containing it. -}
global :: IO (Maybe Repo)
global = do
home <- myHomeDir
ifM (doesFileExist $ home </> ".gitconfig")
( do
repo <- Git.Construct.fromUnknown
repo' <- withHandle StdoutHandle createProcessSuccess p $
hRead repo
return $ Just repo'
, return Nothing
)
where
params = ["config", "--null", "--list", "--global"]
p = (proc "git" params)
{- Reads git config from a handle and populates a repo with it. -}
hRead :: Repo -> Handle -> IO Repo
hRead repo h = do
-- We use the FileSystemEncoding when reading from git-config,
-- because it can contain arbitrary filepaths (and other strings)
-- in any encoding.
fileEncoding h
val <- hGetContentsStrict h
store val repo
{- Stores a git config into a Repo, returning the new version of the Repo.
- The git config may be multiple lines, or a single line.
- Config settings can be updated incrementally.
-}
store :: String -> Repo -> IO Repo
store s repo = do
let c = parse s
repo' <- updateLocation $ repo
{ config = (M.map Prelude.head c) `M.union` config repo
, fullconfig = M.unionWith (++) c (fullconfig repo)
}
rs <- Git.Construct.fromRemotes repo'
return $ repo' { remotes = rs }
{- Updates the location of a repo, based on its configuration.
-
- Git.Construct makes LocalUknown repos, of which only a directory is
- known. Once the config is read, this can be fixed up to a Local repo,
- based on the core.bare and core.worktree settings.
-}
updateLocation :: Repo -> IO Repo
updateLocation r@(Repo { location = LocalUnknown d })
| isBare r = updateLocation' r $ Local d Nothing
| otherwise = updateLocation' r $ Local (d </> ".git") (Just d)
updateLocation r@(Repo { location = l@(Local {}) }) = updateLocation' r l
updateLocation r = return r
updateLocation' :: Repo -> RepoLocation -> IO Repo
updateLocation' r l = do
l' <- case getMaybe "core.worktree" r of
Nothing -> return l
Just d -> do
{- core.worktree is relative to the gitdir -}
top <- absPath $ gitdir l
return $ l { worktree = Just $ absPathFrom top d }
return $ r { location = l' }
{- Parses git config --list or git config --null --list output into a
- config map. -}
parse :: String -> M.Map String [String]
parse [] = M.empty
parse s
-- --list output will have an = in the first line
| all ('=' `elem`) (take 1 ls) = sep '=' ls
-- --null --list output separates keys from values with newlines
| otherwise = sep '\n' $ split "\0" s
where
ls = lines s
sep c = M.fromListWith (++) . map (\(k,v) -> (k, [v])) .
map (separate (== c))
{- Checks if a string from git config is a true value. -}
isTrue :: String -> Maybe Bool
isTrue s
| s' == "true" = Just True
| s' == "false" = Just False
| otherwise = Nothing
where
s' = map toLower s
isBare :: Repo -> Bool
isBare r = fromMaybe False $ isTrue =<< getMaybe "core.bare" r